Improvement in balanced valves



4 Sheets Sheet I.

W. B. CHURCH. Balanced-Valves.

Patented Aug. 17,1875.

w. c. cnuncn. Balanced-Valves.

PatentedAug fi, 1875.

-PETERS. PHOYO-UTHOGRAPHER WASHINGTON. 1 c4 4 Sheets--Sheet 2.

'4Sh eets--Sheet3.

Patented Aug. 17,1875.

W. C. CHURCH.

' Balanced-Valves Illl l 4 Sheets--She6t 4.

W. 6. H U RGH.

Balanced-Valves.

Patented Aug. 17,1875.

MIMI/ t UNITED STATES PATENT OFFIGE.

WALTER CHARLES CHURCH, OF LONDON, ENGLAND.

IMPROVEMENT IN BALANCED VALVES.

Specification forming part of Letters Patent No. [66,848, dated August17, 1875; application filed March 2, 1874.

To all whom it may concern:

Be it .known that I, WALTER CHARLES CHURCH, of 39 Lombard street, in thecity of London and Kingdom of England, engineer, have inventedImprovements in Steam-Engines, (parts of which improvements areapplicable to hydraulic rams and pumps,) of which the following is aspecification The object of my invention (for which a British patent,No. 563, was issued on the 19th day of April, 1872) is a slide-valve forsteamengines, constructed as described hereafter, so as to prevent unduefriction, unequal wear, and: the waste of steam.

I propose, according to my invention, to

. employ a peculiar construction and arrangement of equilibriumslide-valve for steam-engines, such valve being of a circular in lieu oftheordinary rectangular form, and capable of rotating within a circularbuckle or clip, such as is hereinafter described, when running with orwithout steam.

The peculiar construction of slidevalve hereinafterdescribed admits ofthe removal or balancing of the pressure on the valve more effectuallyand easily than when an ordinary rectangular-shaped valve is used. Ipropose to balance or remove the pressure acting on the back of thevalve by the employment of a cap or ring of smaller diameter than thevalve itself, fitting over a junk-ring secured by a central bolt to theback of the valvean Lrshaped packing-rin g, which is equally applicableto pistons ot' steam-engines, rams of hydraulicpresses, pistons andplungers of pumps, and toother similar purposes, being interposedbetween the under side of a projecting flange on the upper surface ofthe said junk-ring and the body of the slide-valve, and pressed againstthe inner parallel bored surface of the l cap and against the junk-ringby the pressure of the steam in the valve-chest, thus making the saidsurfaces in contact steam-tight.

The cap is. kept pressed against the steamtact-surfaces of the metallicpacking-ring.

The pressure of the steam, when in the valve-- chest, against theannular area of the cap nextthe valve keeps the said cap firmly againstthe steam-chest cover, and thus reduces the area subject to pressure onthe back of the valve. The same arrangement of the cap, junk-rin g,S-shaped spring, and metallic packing-ring, used either singly or in.duplicate, may be applied to a rectangular slide-valve. The saidmetallic packing-ring is cut through on one side, and is disposed sothat the surface in actual contact with the internal bored parallelsurface of the cap shall have a less area than the inside annular areaof the said packingring, which is subjected to the direct pressure ofthe steam admitted behind thering, whereby I obtain an excess ofexpanding force tending to press the packing-ring outward against theinternal bored parallel surface of the cap over that which tends topress it inward, and hence I prevent leakage. In conjunction with thisaction the steam also exerts a pressure which forces the reduced annulararea of the packingring against the under or inner side of theprojecting flange of the junk-ring. A segmental joint-piece, such as ishereinafter described, is to be placed across the joint in thepacking-ring, in order to make good the joint and prevent leakagethrough the same.

And in order that my said invention maybe fully understood, I shall nowproceed more particularly to describe the same, and for that purposeshall refer to the several figures on the annexed six sheets ofdrawings, the same letters of reference indicating corresponding partsin all the corresponding figures.

Figure 1 of my drawings represents a trans verse section of asixteen-inch locomotive-engine cylinder with my improved slide-valve.Fig. 2 is a longitudinal vertical section of the same. Fig. 3 is a view01' the back of the improved slide-valve, the cover of the valve-chestbeing removed; Figs. 4 to 7, detached views of parts of the valve.

A is the cylinder, which, with the exception of the steam and exhaustports a a and I), and steam-passages, as hereinafter described, may beof the ordinary construction. 0 is my improved circular equilibriumslide-valve, which is of peculiar construction. It is left free torevolve during its travel within the clip or buckle D on the valve rodor spindle E, by which arrangement the relative surfaces of the valveand portfaces are continually varying, thereby preventing the formationof grooves, and consequently producing a greater uniformity of wear anda longer duration of both valve and port faces, whether worked as anequilibrium or as an ordinary valve. The circular slide-valve may beeconomically made by turning it up and facing it. In the lathe F is ajunk-ring, (shown in detail plan in Fig. 7,) which is also turned in alathe. This ring is fixed onto the back of the valve by a central boltand nut, G. Above and around this junk-ring there is adjusted the loosecap H, also turned up and faced in the lathe, which cap slides againstthe face of the steam-chest cover, thereby preventing the pressure ofsteam or other fluids from acting on the area contained in the insidediameter of the cap H, in contact with the metallic packing-ring g.

A steam-tight metallic packing-ring is established between the junk-ringand the top of the valve and the inner parallel bored surface of the capH by the interposition of the L-shaped packing-ring 9, (shown in detailplan in Fig. 6,) the said ring being forced outward, and at the sametime forced against the under or inner side of the projecting flange ofthe junk-ring, so as to maintain a tight joint and prevent leakage ofsteam by the pressure of the steam in the valve-chest. When the steam isout of the valve-chest the cap H is held in contact with the steam'chestcover by the S-shaped spring I, (shown in section in Figs. 1 and 2, andin plan in Fig. 3,) which spring is placed centrally on a stud or tapturned on the end of the bolt G, while the extremities of its two arms,which are beveled or inclined, so as to fit the inner beveled orinclined surface of the cap, are made to press against such beveled orinclined surface, and, consequently, the horizontal and vertical tensionof the spring forces upward the said cap. The said S-shaped spring canbe cast either in gun-metal, iron, orsteel, or forged out of ordinaryspring-steel, as may be required, and

is made larger in diameter acrossthe arms remaining arm still retainsits elastic action both horizontally and vertically, as, the springbeing bored out centrally to fit on the stud or tap turned on the end ofthe bolt G, it forms a kind of fulcrum for the action of each arm, sothat one can work independently of the other. I have found it necessaryin practice to make the metal of the metallic packing ring or rings 9 ofthe valve much softer than either that of the cap H orjunk-ring F-thatis to say, if the cap H and the junk-ring F are made of gun-metal, themetallic packing ring 9 should be made of soft brass, so as to preventthe outer surface of the metallic packing-ring g from wearing or forminggrooves in the internal parallel bored surface of the cap H, as well asin the surface of the projecting flange of the junk-ring F, by reason ofthe extension and compression of the rings while working. In the centerof the steamchcst cover a pipe, K, is fitted, leading into theatmosphere, such pipe forming the vent for any steam that may escapebetween the cap H and the valve-chest cover, or may leak past thepacking-ring g. A number of holes or radial slots are made round theedge of the junk-ring, as shown in Fig. 7, to allow of the I free escapeof any steam that may momentarily leak past the surfaces of the metallicpacking-ring when the steam first enters the valve-chest, and otheropenings are made through the cap H, such openings communicating with anannular groove or channel, h, Fig. 3, made in the sliding face of thecap, which groove or channel, in conjunction with other channels or sunkparts at t' i, also serves as a free vent for any steam that may leakbehind the cap H when first put to work on the engine.

It will be seen, by referring to the plan, Fig. 3, that the clip orbuckle D, surrounding the circular slide-valve G, is bored out, so as tobe an easy fit over the back part of the valve, to allow the valve torotate freely within it.

The semicircular ends of the buckle D are struck with the same radius asthe diameter of the valve-face 0, each being struck from a separatecenter, for the purpose of giving a greater sectional area onthe-longitudinal cen-' ter line, the section of which is shown in thelongitudinal section, Fig. 2, so as to keep the buckle D from springing,and thereby allow the valve 0 to rotate freely within the buckle Dduring the reciprocal motion of the valve. A flat surface is provided oneach side the total depth of the buckle D, so as to form a guide betweenthe projecting surface h on each side of the steam-chest, to keep thevalve (3 always central over the ports, and thus prevent any lateralmotion of the buckle D by the rotation of the valve 0. These projectingsurfaces h h are suitably faced on the inner side, and also serve toimpart a rotary motion to the slide-valve when traveling without steam,by reason of the periphery of the face of the valve rolling against oneor other ofthe said surfaces. The same rotatory motion of the valve 0 isalso obtained when under steam, if one side of the valve-faceorport-face should become dry for want of more lubrication than theother side, as a greater amount of friction will be caused on that partof the port-face or valve-face through a deficiency of lubrication,thereby creating a greater amount of cohesion between the parts incontact, and by the reciprocal motion of the val e 0 this excess ofcohesion on one side of the valve-face over the other will cause thevalve 0 to rotate in its buckle D, thereby causing a uniformity of wearbetween the surfaces in contact.

masas I a The following proportions of the acting surfaces of themetallic packing-ring g for a twelve-inch circular slide-valveconstructed according to my invention will be foundto answer well inpractice: The outer reduced annular area of the metallic packing-ring gin contact with the internal parallel surface of the cap H is about ninesquare inches, and the inner area of the metallic ring exposed to thepressure of steam in the steam-chest is about thirteen square inches,showing an excess of about four square inches for forcing the outerreduced annular area against the internal parallel bored surface of thecap H by the pressure-of steam in the steam-chest. The reduced annulararea of the metallic packing-ring g on the upper side, next the junkringF, is about six square inches, and the area of the lower side of thering, next the valve exposed to the pressure of steam in thesteam-chest, is about seventeen square inches, showing'an excess ofabout ten square'inches for forcing the upper reduced surface of thering against the projecting flange of thejnnkring F by the pressure ofsteam in the steamchest.

By these means I insure a perfectly tight contact, and thus prevent anyescape of steam or other fluids past the said surfaces when working. Theproportions will vary, and consequently the areas, according to thewidth, depth, and diameter of ring or rings adopted.

Fig. 8 of my drawings represents a transverse vertical section of anordinary rectangular slide-valve, the back pressure on which is avoidedor reduced by the application thereto of my improvements, consisting ofthe junk ring, cap, S-shaped spring, and metallic packing-ring, actingas hereinafter described. Fi 9is a corresponding plan or view of theback of, the slide-valve with the valve-chest cover removed, showing aduplicate arrangement of caps, one cap being in its working position,and the other cap removed. In cases where the rectangular slide-valve isnearly square, a single arrangement of cap, junk-ring, packing-ring, andS-shaped spring maybe used. 0 is the rectangular slide-valve, which isconnected to thevalve-rodE by eyes D D, formed on the back of the valve,through which eyes the rod E is passed, and is secured therein by a'nutat one end, and a loose collar at the other, as shown in plan in Fi 9.

It will be seen that the valve-spindle E is flattened on the top side inthe center part of the valve, as shown in section in Fig. 8, and inplan, Fig. 9, for the purpose of allowing thecaps to be placed closertogether, and thereby obtaining a greater area for displacement of steamon the back of the rectangular valve, due to the inside diameter of thecaps H, or, more strictly speaking, the line of contact between theouter diameter of'each metallic packing -.ring 9 and the internaldiameterv of its cap H. A pair of junkrings, F F, are secured by meansof the bolts Gr G to the back 'ofthe-valve, andincombination with eachjunk-ring there is provided a cap, H, and S'shaped spring I, and ametallic packing-ring, g, all arranged and op- .eratin g precisely asand for the purpose hereinbefore described in reference to the circularslide-valve. K K are the two ventpi1.)es, one for each junk-ring andcap, one of which I have also previously referred to.

When either the circular or the rectangular slide-valve is under steam,the steam in the steam-chest presses upon that part of the annular areaof the cap or caps H next the valve,

which area is due to the difference of its inner and outer diameters 5and as this annular area is greater than that on the top of the cap orcaps H, which is outside the' annular channel or groove h h, Figs. 3 and9, the steam consequently forces the cap or caps H tight against thesteam-chest cover, and by the position and formation of the annulargroove h h any steam-' pressure from small leakage, caused by thesurfaces not accurately fitting one another when first put to work onthe engine, is prevented from being realized on the additional wearingsurfaces on the cap face pressed against the steam-chest cover, andcontained within the annular channel or groove h, since such leakagewill pass off by the channels 11 to the vent pipe or pipes K. Thesurfaces of the cap or caps H and steam-chest cover, after working-for ashort time, will become perfectly tight.

Should. the spring I not force the surface of the cap-face tight againstthe surface of the steam-chest cover when the steam is shut off from thesteam-chest, the moment the steam is readmittedinto the steam-chest thepressure of steam, acting upon the annular area of the said cap or capsnext the valve, instantly forces the cap or caps against the steam-chestcover by reason of the annular area of the cap or caps next the valvebeing greater than the annular area on the cap-face pressed against thesteam-chest cover, which is outside the annular groove h h. All leakageis carried off by the annular groove h h and sank parts t" i, andescapes through the-pipe or pipes K into the atmosphere, as shown on thedrawings, Figs. 2 and 8, there being always a free communication throughthe pipe or pipes K to the atmosphere when the valve 0 is working. as anequilibrium slide-valve, thereby gaining the remaining area or areascontained within the groove h or passages t on the cap-face H foradditional wearingsurface, and diminishing the friction and pressure persquare inch between these surfaces. I thus increase the durability ofthe cap-face, as the total areas of the cap-face sliding on thesteamchest cover are greater than the annular area of the cap H next thevalve, 0, exposed to the steampressure in the steam-chest.

It will be seen from the drawings that the cap or caps H are keptcentral by their inner parallel part fitting over the junk ring or ringsF, either on the circular or rectangular valves,.and are independent andfree to have a rotary motion round the;

junk ring or rings F when traveling Wlbh out steam, especially on1ocom0tive-engines,

since'one side of the S shaped springv will,

in practice, press one side of the cap orf caps H against thesteam-chest coverwith a greater pressure than theother. By this means agreater amount of cohesion is produced between the surfaces. in contact,andby the reciprocal motion of the valve 0 this vexcess of cohesion on.one sideofi-theeap overv theotheriwill canse the caper, caps H to rotatearoundthe junk ring or rings F, thereby causing a uniformityof-wearbetweentheisur:

faces of thecapor caps H antlthe snrfaceof, the.

steam chest covert Thesa ne rotatory motion oti-the cap or caps Hisobtained when, under steam, if one sigle of the cap or caps in contactwith the steam-chest cover should become dry for-[want of lubrication,as at greater-amount; of friction is thereby cansedon that partof.

thecap or caps, thus .creatinga greater amount of 'cohesion between thepartsin contact, and

byl thei reciprocal motion-of thevalve-O this 0f he J'uhhe he fines-1Fwh -sure a a rJm Q m W f ar betw enh r hheh in, 1 act, hesz hapesi nrlle; ttin o e y onto 'a c'e'n max stud o tap tnrne 0n thehead hi otatethtthe cap or capstif required.

y y a ning ot e. l awiaFi e L'Ziahd 8, it will be seen. that,byttheformation of the m hll tcopa khi zrih y eu perr hqedarea of the saidring is pressetl against. the, under side of he innihqt h eh e 9f; heink- 'gQF, istl s} he the r B PQ QfltQstedh, pressure on the du ceglexternal ar eav which. is".presseglagainst the inter'l allparallelbored:surface of themapv or ps. ;ian t thehie ll packih r'ih y' '9, hi h rlso; t h nes e is; a by owh had h theplah, F g- M6 0 mhh h r h h v, lfil w hh hhnlhv rabhet, orrecess, .onth-e top side. of the ring, asshown in I ig ti. The said segmentalpiece heteledt i htly lo i g n re ln th-and.

pth .7 n e thr id 9 at. i s r ht rhr length and depth shall, not, bear;against the.

hidh'lp ir le ir' hhelo -t e a r; ma

thereby. linsnring a uniform 1 contact between a he he b red h zhllelrface ollhhe th n a wllthe 'p h a t pf he u er" acted. area' ofthepaelringging, even should the surfaces. of" the port-face. and ,steam-cl1est cover not be perfeetly parallellg As the segmental" p c 6 is P I hta ihstt e,proi htih flangeofthe junk ring or rings F itv prevents anysteam from escaping at thepar t Where, thecnt in thc ringg is;.made.-The holesor radial slotsin the edge of the junkring, (see Fig. 7,) forcarrying ofl';any 'leakageof steam that may escapepast the surt'aces ofthe me tall ic packing ring or rings 9 throughthe pipe on one sidev overthe other, ,;.0r..caps. torotate around the e ext-[ e alvell h;

;.K in the steam-chest-cover-to the atmosphere,

are so drilled. that the inner edges of these holes orslots are aboutthree: thirty-seconds of an inch clear ofi the outside annular bearing:

snrfaee of the packing-ring, which is. pressed 7 pagalhe e nhoj ct nghhne E he nj nk ring -o'r rings F, so; asto prevent any leakage; st mrpfi lh hr gh he-open ng o ut in the ring g andl whichlis .notcovered'bythe;

segmental piece 0, before described, since, they said segmental piece e,only fills, the recess; =,w. hich is" turned. onv the side; ofthemetallic,

packing ring opringagnext the junkrring,

which .reeess will varyin, widthand depth acqr ihet he ize f h asl p hdhpr s-t e f: teele c n h h an ular m an cap or. caps H-next the valyewill hold them h h h hstthe. eamz es o r n h pressnre, acting oathelarger annular area of;

metallic packingring .Or ringsg .next the valve will hold them alsotight vagainst the-- inner snrfaceofi the projecting flange tot! the .ihhr n ing F, her by pro d n ain any ant Qf' hmlle i lh w enith -m aceand hwh hestlcqven othatby't ee'wl ra cal motion of the valve 0 the capor cap slll ill when hemse resf y r; he-oh ertdim ete of v he, m l ic.packin ne-.o rlnesa and:

hus.ac mihosl ta hms lv w l y n f parallel x' i w i hay e i tvbQtw-eehhe fhhesl f he ot lhqeahs the tea s h stchw er, hereby I reyeh lh t herface flz h.ecan=- 1 org-cap H mz e hg sp eed fromrthe surhhe t z heteahh hestcqy r, nd mut ng-Y ht.p ht ct betwchh 1 t e-s escr ed: a. t wilobe-see ,nnlrh er inette ha rhn n st he ir u ar.v m t hhtah hlanslideal s hetbh .areal-0ni heba wft he-twelve new h m;ihu her= map w e tnh er-v i h ,ohthe cap =or.caps.-H,or, more strictly. 9%.. he;l l qualztthe rQabQuQd Qby h contaet betw. en,;t e outerrdian eter ot'o @QIQQ-pqu, y hepres 9. th e hal ht no a h t L; nthl ihh w n j rill, ;ohr u hyand. the. n e

P T YlSlQh m l n omp esh o n h y u1 6 3- hifllllOQIItDlffiiQ ihhhhhhdabh M l v-F mi a-Ory-an vafifi lll l lfl lq o ldfihsetl;water.infthecylintler when.- the engine is first: u s arted, :h a lQaiwh i i g allewedhetsgeem th t p w th? i nkw ngl hslt e derhlde; of thecap or capsH, alsobetyveenthz.top-side;

of .the valve Q anti/the lower annular edge- 0f he whic or-wps--hepressure o st amr nt hem-s h h-hh st, acbl hn h-n a o er 1 m l,?@:-.0 he iw ps ext the v lv will hol he hldi niorv ap fight ainst-- thesteam-chest. cover, so that when; comprem onto theport-tacewithontmovingthe surface;

.hl ihh eteh f;,thecan awn H-r t l lso-whee ,Figs- ,1, 2 nd v8, hat heris t of the cap-face H from the surface of the steam-chest, cover,thereby preventing the surface of the cap or caps H from being displacedfrom the surface of the steam-chest cover, and insuring a tight contactbetween the surfaces described.

It will be seen, on referring to the drawings, that in my improvedslide-valves there is no communication between that portion of the backof the valve inclosed by the cap or caps H and the exhaust-port b in theport-face of the cylinder for the passage of any leakage that may takeplace from defects in the surfaces of the cap or caps H and metallicpacking ring or rings 9 into the exhaust, as this leakage would passthrough the pipe or pipes K into the atmosphere; but should there be anysuch leakage as would cause a waste of steam from the'engine, theattendant, by closing a tap or taps attached to the pipe or pipes K inthe steam-chest cover, allows the pressure of the steam escaping fromthe steamchest to be exerted on that portion of the back of the valveinclosed within the cap or caps H, thus reducing the valve for the timebeing to an ordinary slide-valve.

In a rectangular valve, (J, supposing one tap only to be closed from thecauses before described, the inclosed area within the cap H would beacted upon by the pressure of steam in the steam-chest; but if both tapswere closed from the causes before described, the pressure of steamwould act upon the back of the valve in the same manner that it wouldwith a slide-valve of the ordinary construction. Thus, it will be seenthat under the most unfavorable circumstances (as in case of accidents)my improved equilibrium slidevalves can never become more objectionablethan the ordinary slide-valve at present in use, as they can either workas equilibrium or ordinary valves until an opportunity can be obtainedfor rectifying any part or parts that may have become deranged, therebyinsuring their certainty of working, in all cases and on all classes ofengines, either as equilibrium or ordinary slide-valves.

The advantages to be derived from the adoption of my peculiar circularequilibrium slide-valves, compared with the rectangular valves now inordinary use, maybe exemplified to a certain extent by taking a circularvalve of twelve inches diameter, as shown in Figs. 1, 2, and 3,containing an area of about one hundred and thirteen square inches onthe back of the valve, having steam-ports for admitting steam on thelead, fourteen inches in length, with an area of about thirteen squareinches, the area of the exhaust-port being about thirty-seven squareinches. The rectangular valve now in use, which is taken as acomparative example, is sixteen inches long and nine and three-fourthsinches wide,

having an area on the back of the valve of one hundred and fifty-sixsquare inches, with steam-ports only thirteen and a half inches inlength, about eighteen square inches area, the exhaust-port being aboutthirty-seven square inches area.

On comparing the above dimensions it will be seen that my circularslide-valves steamport is half an inch greater in length on the lead oropening than the rectangular one, with an area of about forty-threesquare inches less on the back of the valve to be acted on by thepressure of the steam in the steamchest, which diminishes the powerrequired for working it as compared to an ordinary rectangularslide-valve of the dimensions given, at the same time gaining, wheremost required, a large amount of steam-supply to the cylinders, as wellas economizing its consumption by reason of the formationof the portsthrough diminishing the width and length of the steam-passages into thecylinder.

I make no claim in this application to the arrangement of ports shown inthe drawings, as this feature forms the subject of a separateapplication for Letters Patent 5 but I claim- 1. The combination of thereciprocating frame D and the valve 0, having a lateral hearing, by"frictional contact with which an intermittent rotation is imparted, asdescribed.

2. The combination of the valve 0, loose ring H, sliding in contact withthe top of the valve-chest, ring F, secured to the valve, and anL-shaped packing-ring, g, bearing upon the rings F and H, substantiallyas and for the purpose set forth.

3. The packing-ring H, groove h, and channels c i, and recessescommunicating with the groove, as and for the purpose-set forth.

4. The combination of the valve-ring H, having a beveled inner edge, andspring I, bearing against said beveled edge, substantially as set forth.

5. The combination of the valve 0, ring F, and metallic packing-ring g,confined between the two, and reduced to diminish its bearing on thering F, as set forth.

6. The combination, with the L-shaped packing-ring g, adapted tobearing-surfaces at right angles with each other, of the overlappingsegmental piece 6, filling the recess or rabbet on the lateral side ofthe Lshaped ring, all as set forth.

In witness whereof I have'signed my name to this specification in thepresence of two subscribing 'witnesse's.

WALTER CHARLES CHURCH.

Witnesses:

OHAs. thus,

47 Lt'ncolns Inn Fields. FREDK. O. DYER,

47 Lincolns Inn Fields.

